The cable fixing device of this type is employed when inserting a cable through a plate material etc. so as to protect the cover of the cable against damage by the plate material of a chassis of a switch box etc. and at the same time to fix the cable and the plate material firmly, and also it is used in a switch box etc. together with a packing inserted into a housing thereof so as to prevent penetration of rain water etc. through a cable inserting hole.
Therefore, characteristics required of the cable fixing device of this type include that the cable can be firmly fixed, that the fixed cable will not become loose even after it has been repeatedly bent in a mechanical manner, that the fixed part has waterproofness and prevents rain water etc. from penetrating into the inside of e.g. a switch box etc. to which the cable has been installed, that the same cable fixing device can be widely applied to various kinds of cables having different outer diameters, that fixing of the cable can be effected by a simple operation, and so forth. Nevertheless, the conventional cable fixing devices have drawbacks and thus fail to meet the above described characteristics required of the cable fixing devices, for example, some, although they can clamp cables firmly and can withstand repeated, mechanical bending of the cable, have disadvantages that they suffer from poor waterproofness and that they are not widely applicable to cables having different outer diameters because fixing of the cable is given priority in construction; some have a complicated construction in order to enhance fixing of the cable and waterproofness and therefore have a disadvantages that the operation to install a cable is troublesome; some are only applicable to cables having a predetermined outer diameter and whenever they are to be applied to cables having a diameter other than the above, some of the parts have to be replaced, and so forth.